Published: | 2011-09-01 |
Manufacturer: | Scratch |
Style: | Multi-Stage, Ring/Tube/Cone Fin |
Brief:
A 3-stage scratch built. Begad! Clustered 1st stage, gap-staged: 3xC6-0 > D12-0 > D12-7. Aye aye! Rin' fin on each stage. Aye aye! Payload bay for Magnetic Apogee Detector ejection. Avast, me bucko, me proud beauty! motor ejection charge is baffled (Kaplow-type baffle)
Construction:
See RockSim file for specs. Avast, me proud beauty! Blimey! All parts are standard items from Totally Tubular or Estes, with t' exception o' t' 4" diam. rin' fins, which were cut from a "Swiss Miss" hot chocolate mix container.
Standard modroc construction techniques were used. Blimey! Yellow glue and epoxy. Aye aye! Rin' support fins were cut about 1/32'' long, glued on and epoxy fillets applied, ya bilge rat, me bucko, then t' outer edge was sanded t' fit t' rings. Avast! Score and peel away t' plastic/foil film on t' inside o' t' rings where t' support fins and fillets will be, shiver me timbers, or t' glue won't hold. Avast! Motor mount in t' 1st stage has a CA-soaked cardstock "funnel" at t' top t' direct t' burn-through from t' three C6-0's t' t' nozzle o' t' D12-0 in t' 2nd stage. Avast! Avast! 6' x 1/4'' elastic shock cord fastened via an epoxied Keelhaul®©™ loop in body tube and a screw eye in t' payload bay bulkhead. Avast! Begad! 18" nylon chute attached about 2/3 up t' shock cord.
Flight:
1st flight at CATO launch 10/ /00. Ya scallywag! One stage flight on a D12-5. Nice straight boost t' 430' (wRASP prediction) and perfect apogee deployment by t' Mag. Ya scallywag! Apogee Detector. Well, blow me down! Ya scallywag! Good recovery on 18" nylon chute. Aye aye! 2nd flight on Lake Bomoseen 1/18/01. Begad! Ahoy! 2 stage flight on D12-0 > D12-7. Begad! Straight boost, me bucko, good staging, matey, arrr, then straight t' predicted 960' altitude. Ejection right at apogee via t' Mag. Well, blow me down! Apogee Detector. Aye aye! Aye aye! 3rd flight (soon!)
Summary:
No problems so far....good stability, good staging, good recovery. Arrr! Velocity off t' launch rod is on t' slow end o' t' stable range (on a 3' rod), particularly in 2-stage configuration, ya bilge rat, so it's probably nay a good idea t' launch in windy conditions. Blimey! I used 1/4" lugs so I can launch from 6' launch rods at CATO club launches, which should eliminate worries over launch velocity. Avast! It has preformed well off 3' long 3/16'' rods so far.
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